Motor jack



Nov. 19, 1940. w. J. Nx-:LsoN '2,221,343

MOTOR JACK Filed Feb. 27, 1959 2 Sheets-skelet 2 1NvENroR.

ZHLZz/mJ/Veiom BY J DW ATTORNEY.

Patented Nov. 19, 1940 UNITED STATI-:s

PATENT MOTOR JACK William J. Nelson, Oak Park, Ill., assignor to Jay E.

Burns, Trustee, Chicago, Ill

Application February 27, 1939, serial No. 258,712

Claims.

My invention relates to jacks, more particularly of the type having a motor base, the jack standard being carried by a vertically movable piston adapted to be raised by fluid pressure. 5 Such a device in which the motor piston is repeatedly raised and lowered by supplying and releasing fluid pressure to and from the. cylinder space under the piston, whereby to reciprocate the jack standard and load thereon, may be advantageously used for rocking or vibrating an automobile body in relation to its supporting springs to promote eiective penetration of grease into the spring joints and shackles and. between the leaves of the springs. The present l invention provides improvements contributing to practicability, efficiency and convenient utility of an automobile rocker jack or other jack of the motor base type, particularly in the case of a 2 tall sectional jack to be used in a lubricating pit vated position on a lift or overhead runway.

A feature of the invention is a novel construction for an extensible jack comprising telescoping sections and carrying a jack screw operable E25 by rotation of the upper section of the jack :35 clined floor, as on the portion of the floor of a lubricating pit adjacent the central drain of the pit. Among other features is the provision of means to enable the weight of the device to be transferred to rider wheels normally clear of 310 the floor, so as to render the device easily portable and to enable it to be quickly shifted into position for operative use.

One practicable device embodying the invention is shown for illustration in the accompany-A ing drawings, in which:

Fig. 1 is av side elevation of the illustrative device. Y

Fig. 2 is a sectional plan view taken on the line 2-2 of Fig. 1, looking in the direction of the arrows.

Fig. 3 is an enlarged vertical section through a portion of the illustrative device, taken on the line 3-3 of Fig. 2, looking in the direction of the 55 alIOWS.

Fig. 4 is a horizontal section through the motor base, taken on the line 4-4 of Fig. 1 and showing the portion of the structure below the line in top plan View.

'60 Fig. 5 is a central vertical section taken onthe or beneath an automobile supported in an eleline 5 5 of Fig. 4, looking in the direction of the arrows.

Fig. 6 is a view corresponding to Fig. 4 showing a modification with respect to the supporting p base of the device. `5

Fig. 7 is a vertical section taken on the line 1-1 of Fig. 6.

Figs. 8 and 9 are sectional views representing modications with respect `to the manner of mounting the jack standard. 10

Referring to Figs. 1 to 6, the illustrative device therein shown is an automobile rocking jack comprising a fluid operated motor and a tall extensible jack standard carried by the motor piston.

vIn the drawings, I0 denotes the motor cylinder, 15

closed at its upper and lower ends by the heads II and I2; and I3 is the motor piston, whose upwardly extending piston rod I4 is guided in the central sleeve boss I5 of the upper cylinder head. In operation, the piston is raised by fluid pressure thereunder, and lowered by the weight or load thereon as the pressure is relieved through a restricted exhaust passage. Motors of the type for a rocker jack are known to the art. Such motor may be operated by compressed air, being equipped for connection with a source of oompressed air and having suitable valve mechanism for controlling admission and exhaust of motive fluid to and from the lower end of the cylinder for causing reciprocation of the piston, preferably at a rate of about from 20 to 30 reciprocations per minute. A.

Mounted on and affixed to the piston rod as a continuation thereof is the tubular jack lpost I6 constituting the lower section of an extensible standard whose upper section or strut Il, telescoping in the lower. section, is carried by and rotatable with a hand wheel I8 swivelled to the upper end of the lower section. Ihe upper section or strut I1 has an axially bored and inte- 40 riorly threadedupper portion I9 engaged by the jack screw 20 on which is non-rotatably mounted the jack head or saddle 2|. It may be assumed that the-device sets on the floor of a pit beneath an automobile standing thereover, or that the device is mounted beneath an automobile supported -in elevated position on a lift or overhead runway, andthat the jack is adjusted to bring the saddle 2I into engagement with thecentral member or one of the end members or side mem- 5o bers of thev automobile chassis frame, or that the saddle 2l carries thereon a removably mounted top saddle 22 which is .brought into engagement With the central members 23 of the type of chassis frame for a Ford car. The hand wheel I8 55 may now be rotated to feed the jack screw upwardly, so as to lift the chassis or supported part thereof in relation to the vehicleisprings; and the motor may then be operated to reciprocate the jack structure carried thereby, thus rocking or m vibrating the chassis or vehicle body in relation to its supporting springs.

In order to permit the jack to be quickly extended and conveniently operated for feeding the jack screw, the jack standard embodies the construction shown in Figs. 2 and 3, wherein the upper section or strut I1 is slidably and nonrotatably fitted in the hub of the hand wheel I8 and is formed or constructed as a ratchet bar engageable by a pawl or pawls carried by the hub of the hand wheel; the arrangement of the ratchets and pawls being such as to permit the jack section or strut I7 to be lifted and held in the position to which it is elevated. In the specific construction shown, the strut I1 below the portion thereof carrying the jack screw is substantially square in cross section but with rounded corners, as shown in Fig. 2, being vertically slidable in a correspondingly formed opening in the hand wheel hub 24, and such rounded corners being slidably or loosely fitted in the tubular jack post l 6. The strut I7 is shown having longitudinal ratchets 25 on opposite sides, but the invention contemplates a construction in which the strut i1 has a single ratchet on one side only. The teeth of the ratchets 25 are presented downwardly and engaged by the upper ends of the pawls 26 which are pivotally mounted on pins or pintles 21 between ears 28 on the hand wheel hub. Near their ends in engagement with the ratchet teeth the pawls are supported on shoulders 29 on the hand wheel hub, thus taking the weight from the pawls close to the ratchet bar strut. The hand wheel hub bears rotatably on the cap 38 fastened on the upper end of the jack post I5, said hub being shown formed with a depending flange or skirt portion 3| enclosing said cap and having pins 32 (Fig. 2) engaging an annular groove 33 in said cap to provide a swivel connection for the hand wheel. The ratchet pawls 26 are spring-held in engagement with the ratchet teeth by springs 34 interposed between the skirt portion of the hand wheel hub and tail extensions 35 of the pawls, said tail extensions being formed to provide handles 3S. By means of such handles, which extend below the hand wheel, the operator can safely disengage the pawls from the ratchet bar strut l1 after the hand wheel has been operated to feed the jack screw downwardly sulciently to be relieved of the load.

A device of the class described must sometimes be mounted over a drain in a lubricating pit or on an inclined iioor adjacent to or near the drain, in which event, unless the operator goes to the trouble of providing wedges or shims under the motor base, the jack standard will 'be out of plumb or in a tilted instead of a perpendicular position, so that there will be danger of tilting over the device under the action of the load thereon, particularly in the case of a rocker jack. To obviate this difficulty, and to avoid the necessity of propping up or shimming the motor base to hold the jack standard erect, I have provided a novel motor base structure embodying separate members bearing one upon another and having contacting spherical bearing surfaces, or at least one of said members having a convex surface in bearing contact with the other, with connecting means between the members allowing a limited angling of the upper member relative to the lower member, so that the jack standard can be established in erect position notwithstanding that the motor base rests on an inclined support.

As shown in Figs. l, 4 and 5, the lower cylinder head I2 is formed with a concave bottom surface which bears on a convex upper surface 48 of a separate base member 4 l, said base member having the under side of its central portion spaced from the floor. Said cylinder head and base member are connected by the bolt-screw 42 engaging a tapped hole in the cylinder head and passing through an opening 43 in the base member, the

head of the screw or the washer 44 engaging the as to prevent accidental separating of the parts.

The rim portion of the base member is formed on its under side with three appropriately spaced flat-bottomed feet 48, of only slight elevation, thus providing a three point support whereby to avoid wobbling if the device sets on an uneven floor surface. A pair of rider wheels are shown at 45, whose axle 46 is mounted in lugs or ears 4l projecting laterally from the base member. These wheels are carried by the base member adjacent to one edge thereof and just clear of the floor, so that they do not normally afford a roller support; but by tilting the motor jack toward the rider wheels they are brought into contact with the oor and take the weight of the device, so that it can be readily shifted from one position to another.

In Figs. 6 and 7, showing a modification of the 'base structure, the lower cylinder head designated by the numeral H6 is formed with a bottom convex bearing member 5U which bears in the upper concave surface of the separate base member 5|. In this instance the cylinder head is shown formed with lateral lugs 52, which engage under an overhanging flange 53 on the base member to connect the parts together, said flange having notches 54 to permit insertion of the lugs therethrough. It will be understood that in assembling the structure of Figs. 6 and 7 the parts are held in such relation as to register the lugs 52 with the notches 54, and after the lugs are inserted through the notches the base member and cylinder are turned one relative to the other to engage the lugs under the flange 53. Sucient clearance is allowed between the lugs and flange to permit limited angling of the motor cylinder and jack standard on the base member.

In Figs. 8 and 9, constructions are shown whereby, instead of mounting the cylinder on a separate base member, the lower section of the jack standard can be mounted on the motor piston rod in a manner to permit the standard to be held erect when the motor base rests on an inclined supporting surface. In Fig. 8, the numeral 2 I4 designates the motor piston stem or rod, and the numeral 2 i6 designates the jack post or lower section of an extensible jack standard such as already described; these parts typifying sections of the jack structure as a whole, whose adjoining ends are in the lower part of the structure. Fast on the upper end of the lower section or piston rod 2|4 is a bearing member 60 having a convex bearing surface. Enclosing and rigidly secured to the end portion of the other section or jack post 2l6 is a sleeve El formed therein with a bearing member 52 which bears on the member Sil; said sleeve having an extension enclosing the end portion of the section 2|4, and there being sufficient clearance at 63 between the sleeve and relative to the lower of section 214 to allow a limited angular movement of the jack standard relative to the piston rod.

A connection between the parts is provided by the screw 613, the hole therefor in the member 62 being suiiciently large to allow the member 2 to assume different angular positions on the member` to. in lieu of the specic construction of Fig. 8, a reversal thereof may be used.

In Fig. 9, the numerai 3M designates the motor piston rod and Sie denotes the jack post. Their adjoining ends have the contacting bearing members 'ifi and i i, one or both of which may have a convex bearing surface. A sleeve 'l2 encloses the adjoining end portions of the jack sections Sil and SES, said sleeve being connected with said sections by the pins 73. Clearance is provided between the sleeve and jack sections, and in the pin holes in the sections, allowing limited relative angling.

It will be observed that the constructions of Figs. 4 and 5 and those of Figs. 6 to 9 exemplify different specific constructions in a jack embodying in its lower portion separate members one of which is mounted directly on the other, the lower of said members having an upwardly facing bearing surface and the upper of said members having a bo-ttom bearing surface bearing on rst mentioned surface, at least one of said surfaces being convex to permit lthe upper of said members to assume different angular positions said members, whereby the principal portion of the structure above said contacting bearing surfaces can be established in erect position when the base of the structure rests on an inclined supporting surface, and connecting means between said members allowing a limited angling movement of the upper of said members relative to the lower of said members. The members here referred to are the cylinder and separate base member in Figs. 4 and 5, the members 6U and t2 in Fig. 8, and i9 and 'H in Fig. 9.

The term motor jack is intended to apply either to an automobile rocking jack or one whose motor piston reciprocates the jack standard with the load thereon or to one whose motor operates to raise the jack standard with its supported load by iiuid pressure and to sustain it in raised position until release of the fluid pressure at the will of the operator.

Embodiments of the invention in such modified forms as may be within the scope of the following claims are intended to be secured.

I claim as my invention:

l. A motor jack having telescoping jack sections, the upper section being slidable and rotatable in the lower section, a hand wheel rotatably mounted on the upper end of the lower section, the upper section having a longitudinal ratchet and being slidably but non-rotatably tted in the hub of said hand wheel, whereby rotation of the hand wheel will rotate the upper section through direct driving engagement therewith, pawl means carried by said hub coacting with said ratchet, said ratchet and pawl means being arranged to permit lifting the upper section in said hub and to support it in the position to which it is elevated, and an axially arranged jack screw in threaded engagement with the upper section, said screw adapted to be fed by rotation of said upper section by said handwheel.

2. A motor jack having telescoping jack sections, the upper section being slidable and rotatable in the lower section, a hand wheel rotatably mounted on the upper end of the lower section, the upper section having a. longitudinal ratchet and being slidably but non-rotatably fitted in the hub of said hand wheel, whereby rotation of the hand wheel will rotate the upper section through direct driving engagement therewith, a pawl mounted in said hub and spring pressed in engagement with said ratchet, said ratchet and pawl being arranged to permit lifting the upper section in said hub and to support it in the position to which it is elevated, said hub having a portion adjacent to the ratchet on which the pawl rests when supporting said upper section, and an axially arranged jack screw in threaded engagement with the upper section, said screw adapted to be fed by rotation of said upper section by said hand wheel.

3. A motor jack having telescoping jack sections, the upper section being slidable and rotatable in the lower section, a hand wheel rotatably mounted on the upper `end of the lower section, the upper section having a longitudinal ratchet and being slidably but non-rotatably fitted in the hub of said hand wheel, whereby rotation of the hand wheel will rotate the upper section through direct driving eng-agement therewith, a pawl mounted in said hub and spring pressed in engagement with said ratchet, said ratchet and pawl being arranged to permit lifting the upper section in said hub and to support it in the position to which it is elevated, said hub having a portion adjacent to the ratchet on which the pawl rests when supporting said upper section, and an axially arranged jack screw in threaded engagement with the upper section, said pawl having a depending tail portion providing a downwardly extending lever handle under said Wheel by which to operate the pawl to disengage it from the ratchet, said screw adapted to be fed by rotation of said upper section by said hand wheel.

4. A jack including vertically disposedl sections in end to end relation and whose adjoining ends are in the lower part of the structure, a sleeve rigid with and enclosing the end portion of one of said sections and extending therefrom and loosely enclosing the end portion of the other section, said other section having a bearing member on its end, said sleeve having an internal bearing member between its own ends and between the ends of said sections, said members bearing one on the other and having contacting spherical surfaces, there being sufficient clearance `between said sleeve and said section which has a bearing member on its end to allow a limited angling of one section relative to the other, and connecting means between said sections allowing such limiting angling,

5. A jack embodying vertically disposed sections inend to end relation and whose adjoining ends are in the lower part of the structure, said sections having bearing members on said ends, one bearing directly on the other, at least one of said members having a convex bearing surface, a sleeve loosely enclosing the end portions` of said sections, and pins transxing said sleeve and sections, each pin being loose in one of the elements with which it is Connected.

WILLIAM J. NELSON. 

